1. Technical Field
The present invention relates to a profile creation method and a computer readable recording medium stored with a profile creation program.
2. Description of Related Art
In creating a printer profile for an electro-photographic printer, the printer is caused to output patch images having colors corresponding to combinations of values of C (cyan), M (magenta), Y (yellow), and K (black) to correlate the CMYK values of the patch images with colorimetric values (such as L*a*b* values) thereof. Since it is difficult to output patch images of all combinations of all values of C, M, Y, and K to perform colorimetry, the printer is usually caused to output a color chart including an array of about several hundreds of patch images. Then, for a color conversion LUT (lookup table) indicating a correspondence relationship between the CMYK values of the patch images and the colorimetric values thereof, a grid-point interpolation process is performed to create a color conversion LUT having a predetermined number of grid points.
With regard to this, Japanese Unexamined Patent Application Publication No. 2013-219522 discloses a technique for creating a color conversion LUT having a predetermined number of grid points by performing an interpolation process using an optimal interpolation method for each grid point selected from among a plurality of interpolation methods. This technique improves interpolation accuracy for the grid points of the color conversion LUT, thus allowing improvement in accuracy of a printer profile created by outputting a color chart.
However, the above technique does not consider the influence of variation in colors (reproducibility) output from a printer. Colors output from a single printer slightly vary per output even in colors of the same CMYK values. In addition, colors output from a plurality of printers slightly vary per printer even in colors of the same CMYK values output from the printers of the same model. The degree of such a color variation per output or per printer varies depending on the color to be output.
Accordingly, under the recent circumstances where achievement of higher precision color management has been desired, there has been a concern that when a printer profile is created on the basis of one sheet of a color chart output by a printer, color variation is picked up, thus creating a rather inappropriate printer profile. When considering color variation per output and color variation per printer, it is preferable for a printer profile to reflect an average value (median value) of color variation.